1. Field of the Invention
The present invention relates to a multi-way selector valve, e.g., a three-way selector valve or a four-way selector valve, used for a refrigerating cycle, or the like. More particularly, the present invention relates to a rotary type multi-way selector valve properly used on a vehicle, where a valve body is rotated by an actuator having a planetary gear type speed reduction mechanism to switch a flow path.
2. Description of the Conventional Art
A refrigerating cycle such as an air conditioner or a refrigerating device generally includes a four-way selector valve which is a flow path (flow direction) selection means, in addition to a compressor, a gas-liquid separator, a condenser (an outdoor heat exchanger), an evaporator (an indoor heat exchanger), and an expansion valve.
One example of the refrigerating cycle having the four-way selector valve will be described with reference to FIGS. 12 and 13. A refrigerating cycle 300 illustrated in the figures is for an air conditioner, and switching of operation modes (a cooling operation and a heating operation) is made by a four-way selector valve 320. The refrigerating cycle 300 includes a compressor 310, a gas-liquid separator 312, a condenser (an outdoor heat exchanger) 314, an evaporator (an indoor heat exchanger) 316, and an expansion valve 318. The refrigerating cycle 300 has the four-way selector valve 320 between the compressor 310, the gas-liquid separator 312, the condenser 314, and the evaporator 316, and the four-way selector valve 320 has four ports, i.e. first to fourth ports (inlets/outlets) a, b, c, and d (refer to FIG. 13).
These devices are connected each other by a flow path made of a lead pipe (a pipe). More particularly, the refrigerating cycle includes a suction flow path 321, a discharge flow path 322, a condenser-side push return flow path 323, an evaporator-side push return flow path 324, a return flow path 325, a flow path 326, and a flow path 327. The suction flow path 321 introduces a refrigerant in the gas-liquid separator 312 into the compressor 310. The discharge flow path 322 introduces a high-pressure refrigerant discharged from the compressor 310 into the first port a of the four-way selector valve 320. The condenser-side push return flow path 323 connects the second port b of the four-way selector valve 320 with a first distribution port 314a of the condenser 314. The evaporator-side push return flow path 324 connects the third port c of the four-way selector valve 320 and a first distribution port 316a of the evaporator 316. The return flow path 325 connects the fourth port d of the four-way selector valve 320 and a return port 312a of the gas-liquid separator 312. The flow path 326 connects a second distribution port 314b of the condenser 314 and the expansion valve 318. The flow path 327 connects the expansion valve 318 and a second distribution port 316b of the evaporator 316.
In the refrigerating cycle 300 having the aforementioned configuration, when a cooling operation mode is selected, the four-way selector valve 320 switches the flow paths in a state in which the discharge flow path 322 communicates with the condenser-side push return flow path 323 and the evaporator-side push return flow path 324 communicates with the return flow path 325, as illustrated in FIG. 13 (A). At this time, as illustrated with a solid line arrow in FIG. 12, the compressor 310 sucks a low-pressure refrigerant in the gas-liquid separator 312 through the suction flow path 321. A high-temperature and high-pressure refrigerant is introduced from a discharge port 310a of the compressor 310 to the condenser 314 through the discharge flow path 322, the four-way selector valve 320, and the condenser-side push return flow path 323. The condenser 314 condenses the refrigerant by heat exchanging with an outdoor air, and makes a two-phase high-pressure refrigerant. The two-phase high-pressure refrigerant is introduced to the expansion valve 318 through the flow path 326. The expansion valve 318 reduces a pressure of the high-pressure refrigerant. The pressure-reduced low-pressure refrigerant is introduced to the evaporator 316 through the flow path 327. The evaporator 316 evaporates the refrigerant by heat exchanging (cooling) with an indoor air. The low-temperature and low-pressure refrigerant returns from the evaporator 316 to the gas-liquid separator 312 through the evaporator-side push return flow path 324, the four-way selector valve 320, and the return flow path 325.
On the other hand, when a heating operation mode is selected, the four-way selector valve 320 switches the flow paths in a state in which the discharge flow path 322 communicates with the evaporator-side push return flow path 324 and the condenser-side push return flow path 323 communicates with the return flow path 325, as illustrated in FIG. 13 (B). At this time, as illustrated with a broken line arrow in FIG. 12, the compressor 310 sucks the refrigerant in the gas-liquid separator 312 through the suction flow path 321. The high-temperature and high-pressure refrigerant is introduced from the discharge port 310a to the evaporator 316 through the discharge flow path 322, the four-way selector valve 320, and the evaporator-side push return flow path 324. The evaporator 316 evaporates the refrigerant by heat exchanging (heating) with an indoor air, and makes a high-pressure two-phase refrigerant. The high-pressure two-phase refrigerant is introduced to the expansion valve 318 through the flow path 327. The expansion valve 318 reduces the pressure of the high-pressure refrigerant, and the pressure-reduced low-pressure refrigerant is introduced to the condenser 314 through the flow path 326. The condenser 314 condenses the low-pressure refrigerant by heat exchanging with an outdoor air. The low-temperature and low-pressure refrigerant returns from the condenser 314 to the gas-liquid separator 312 through the condenser-side push return flow path 323, the four-way selector valve 320, and the return flow path 325.
Japanese Patent Application Laid-Open No. 2001-295951 discusses a rotary type four-way selector valve to be assembled in the refrigerating cycle as aforementioned. The rotary type four-way selector valve basically includes an actuator for switching flow path, a valve body rotated by the actuator, and a main valve body. The main valve body rotatably holds the valve body, and has a valve seat section and a valve chamber. The valve seat section of the valve main body includes a first inlet/outlet (a condenser communication port), a second inlet/outlet (an evaporator communication port), a high-pressure inlet for introducing a high-pressure refrigerant from the compressor discharge side into the valve chamber, and a low-pressure outlet for deriving a low-pressure refrigerant to the compressor suction side. The four-way selector valve switches the flow paths by rotating the valve body, to make one of the first inlet/outlet and the second inlet/outlet selectively communicate with one of the high-pressure inlet (the valve chamber) and the low-pressure outlet.
Further, as for the flow path switching actuator, a type of an actuator which directly rotates the valve body by a motor including a rotor and a stator is well known. In addition, Japanese Patent Application Laid-Open No. 8-327183 discusses an actuator which pulls the valve body by a solenoid and a plunger to rotate the valve body.